Homework Help
by forlornwriter
Summary: L/Sayu. Light's friend was a weirdo, Sayu realized. But he was a smart weirdo. Plus, he was nice enough to help her with her homework. And so she grew to like her brother's weirdo friend. A little more than she should have.
1. Algebra

**CHAPTER ONE** | _ALGEBRA_

Sayu had met him on a Sunday.

She had been sitting in the living room with her homework, biting the eraser of her pencil with a pensive frown on her face. She had spent Friday and Saturday hanging out with friends and lazing about at home, having ignored her homework, and now that it was almost Monday, she finally pulled out her homework.

It was the dreaded _math _homework, and they were learning something stupid having to do with letters. Algebra, it was. However, Sayu really could care less what it was called, to be honest. It was still confusing.

Normally, Sayu would ask her brother, Light, for help with her homework. But Light was out with some girl in his class. Sayu smiled at the thought of her. The girl was really pretty; dark brown hair with brown eyes and a cheerful smile. Sayu wouldn't mind if she became her brother's girlfriend; she was rather nice and seemed smart enough for Light.

Then again, Light was the smartest in his class. The smartest in the whole school, even.

But whatever. The thing was that he was out and this meant that she couldn't ask him for help with her homework. And who knows how long Light would stay out because of the date, although Sayu knew he would come back before midnight.

He _always _came home from a date before then, not wanting their mother to worry.

This was fine, but the problem was that Sayu wanted to get her homework _done and finished _before then! She was already feeling sleepy, and it just turned nine. Imagine how sleepy she would be around midnight!

Sayu groaned, running a tired hand through her hair, pouting. She really should've known better! She _should've _finished her homework before Sunday! Light had _told _her she should do finish her homework on Saturday. He had _told _her. But no. She didn't listen to him, too busy watching her favourite drama to care about what he was saying. And now she had to suffer the consequences of her actions.

Before she could self-deprecate any further, the doorbell rang. Furrowing her eyebrows, Sayu looked up from her work, lying across the three-seater couch in the living room as she usually did.

"Sayu, could you get the door?" called her mother from the kitchen.

"Okay, okaa-san*!" Sayu said back, jumping off of the couch and dashing to the door. Who was it? It couldn't be Light, since he left just about half an hour ago, and his dates went on longer than that. Maybe something happened?

Extremely worried, Sayu quickly opened the door and realized immediately who it was.

It was Light's weirdo friend. The one with with the dark, messy hair, eyes that resembled bottomless pits, and weird, hunched over posture. Oh, and he didn't wear any shoes or socks and talked in a monotone voice while wearing the same type of clothing _(or, eww, maybe even the same clothes!)_.

He was, in short, a weirdo. And much less handsome than her brother, that's for sure.

She tilted her head to the side, blinking. "Are you looking for my brother?" she asked him, keeping the doorknob firmly in her grasp so she could close it quickly on his face if she had to. Something about him made him seem really..._shady_. She had no idea why Light was friends with someone as creepy looking as him.

"Yes," he replied, shoving his hands in his pockets. "May I ask if he is present?"

Sayu shook her head. "Nope. He's on a date right now," she informed him. "Do you want me to let him know you came over?"

He blinked. "No, it's fine. I'll stay over at your residence for a while to wait for him, if that is alright?"

Sayu wanted to say that no, it's not alright, but she knew that Light wouldn't be happy with her if he found out she had been so rude to one of his friends. That was the only reason why she didn't say it even though she really wanted to so the weirdo would leave her alone to wallow in pity and self-deprecation.

Instead, she said, "Uh...he won't be here for a few hours..."

"It's fine. I do not mind waiting for him."

She bit her lip and relented. "O-Okay, then. Come on in...?" It came out as more of a question, and she opened the door wider and stepped to the side to allow him entry.

He hovered a bit on the porch, as if not wanting to come in, before stepping in. He wiped his feet a bit on the carpet, shuffling awkwardly with his back bent weirdly before walking into the living room towards the couch opposite the one she had been lying on previously.

"Who was it, Sayu?" asked her mother from the kitchen.

Sayu closed the door, locking it, and entered the living room. "I-It's anii-chan's** friend! He's going to wait a bit for ani-chan to come back from his date."

"Oh!" exclaimed Mother, and hurried into the kitchen with a wide smile. It fell a bit when she saw Light's weirdo friend, realizing which friend Sayu had been talking about, before smiling more widely.

Sayu wanted to giggle because she could tell the smile was forced but tried her best to hide her chuckles back by coughing. Her mother wouldn't be happy with her if she openly laughed, and Light's friend might think they were being really rude and tell Light of it. And Sayu didn't want Light to be angry with her.

"Would you like anything?" her mother asked as warmly as possible.

Light's friend sat on the couch in his weird way; well, it was more like _crouching _on it than actually sitting, and brought his thumb to his lips as if he were some sort of baby.

"Do you have anything...sweet?" he asked in that weird voice of his. His voice was rather soft and quiet, but he sounded so _emotionless_. It brought shivers to Sayu's spine. She tried to suppress them as she sat down gingerly next to her homework.

The only reason she even did so was because she decided he would probably know that she didn't like being around him if she suddenly gathered her things and left. So, in short, it was probably best if she sat and acted as casual and normal as possible. Even though she was a horrible actress and even worse at lying.

Ignoring the short, awkward conversation Light's friend was having with her mother, Sayu went back to her homework, pouting as she looked over the questions that she had no answers to. Why _were_ there so many questions anyway? Why did her teachers enjoy thrusting pages upon pages of homework during the weekend? Weekends were for enjoying and relaxing, not for doing stupid homework!

Sighing heavily in useless angst and picking up her pencil, she began to doodle along the margins of the page when she heard Light's friend shuffling about on the couch, drawing her attention away from her homework for a few seconds.

She glanced up through her eyelashes to see him staring around the room, biting on his thumbnail as he did so, his bangs casting a creepy shadow over his eyes. Her mother had long-since left to the kitchen, probably to fix up 'something sweet' like Light's friend wanted. Sayu glanced back down and continued to doodle.

A few minutes passed by in awkward silence.

However, eventually Sayu realized that she would _never _get her homework done at this point if she continued to doodle, so she attempted to read the questions again.

And...nothing.

Sighing once more, she wiggled back on her couch, crossed her legs at her ankles and tapped the eraser of her pencil against her page.

Just out of curiosity's sake, she snuck another look at Light's friend. And then she had an epiphany.

Light was very smart, and he wasn't the type of person who would befriend airheads. That meant that he would have to have friends who were smart. Not as smart as him, perhaps, but smart nonetheless. So maybe...Light's friend could help her with her homework?

She had seen him before at the house, too. He had come four or five times, and once he had even stayed over for dinner. It had been rather awkward, especially since her father kept on staring at Light's friend with a small frown on his face and, weirdly enough, fear in his eyes. Maybe her father found Light's friend creepy too? Who knows.

This didn't matter, though. What mattered was that she had seen him around the house and had been present when he interacted with Light and sometimes her father. He didn't sound dumb or like an airhead. In fact, he sounded rather factual and constantly was sprouting off percentages for some weird reason. He _had_ to be smart, _especially_ if he was in the same university as Light's. Her homework was probably child's play in his weird, beady eyes.

Sayu tentatively bit her lip before asking, "Uhm...do you know math?"

Immediately she felt her slapping herself.

What kind of a question was _that_? _"Do you know math?"_ Of course he knew math!

Still, her brother's friend did not laugh at her or even make fun of the question. Instead, he seemed to study her, biting away at his thumbnail.

"...yes," he answered after a few seconds of nothing.

She scratched the back of her head. "D-Do you mind...helping me?" she asked sheepishly. "Usually I'd ask my brother, but like I told you, he's on a date."

He blinked once, twice, before saying, "I don't mind aiding you with your homework."

Sayu beamed at him, thankful. "It's algebra, and I really don't know algebra. It's all confusing and has letters in it, which makes no sense since math is supposed to be numbers," she rambled, getting up from the couch and sitting next to Light's friend. He seemed to tense a bit before relaxing some and simply staring down at her.

"Alegbra uses letters because the letters represent a number," he explained calmly. "You have to do a series of steps to find the number that the letter represents."

"Yeah, I know that, but still. It seems weird either way."

"Math isn't about all about numbers, Yagami-chan. You need words to explain the steps you used and for therefore statements. Language is an essential tool, especially in math, as you need language to get your point across and explain your ideas."

"That's true," Sayu murmured, nodding her head slowly. "Uhm...here is my homework..." She tilted the pages in her hands so her brother's friend to look at them. He stared at the homework, biting his thumbnail still as he did so.

"This should be easy enough to explain," he said to her, and began helping her. It was a bit difficult to understand what he was saying at times because the words he used were a bit confusing for her to comprehend, but over time Sayu began to understand better.

It was almost as if it was Light teaching her algebra rather than his friend, although their tone of voice was complerely different. Light's voice was more warm, filled with more feeling. His friend's, however, was monotone and more _to the point_. Still, their methods of teaching, and even their ideas appeared to be very alike. It was almost kind of weird.

Eventually, Sayu's mother entered the living room holding a plate of cookies, eyes widening in surprise to see Sayu sitting next to Light's friend. She seemed almost nervous, but when she noticed that he was only helping her with homework, she appeared to be less nervous.

"Here are some cookies," she said, placing the plate down on the table that was in front of them. "I hope you like them."

"Thank you," he murmured, reaching over to grab a cookie. He held it gingerly with his thumb and index finger, as if holding with all of his fingers would cause it to crumble into nothing. Sayu raised an eyebrow at this, finding it kind of weird, but brushed it off. Hey, he was kind enough to help her out with her homework. Who _cares_ how weird he may act.

"I'm in the kitchen if you two need anything else," her mother said, biting her lip before smiling weakly.

"Gotcha, okaa-san!" Sayu said, beaming at her mother. This seemed to make her mother feel better, and she left with a more confident smile on her face.

And then Light's friend went back to helping her with her homework.

* * *

About an hour or so passed until Sayu had completely finished her math homework and was sure that she fully understood what all of the questions asked of her. In fact, algebra seemed rather easy to her now. She hoped that it would stay that way.

After having finished placing her work back into her backpack, she turned towards Light's friend. "Are you going to stay here longer to wait for my brother? It's probably going to take two or more hours for him to come back."

He stared at her, biting his thumbnail, before shaking his head and getting up from the couch. "I will be taking my leave now. Thank you for your hospitality, Yagami-chan."

Sayu blushed. "W-Well, I should be thanking you. So uh, thank you for helping me with my homework!"

"You're welcome," he murmured. "Do say thank you on my behalf to your mother. For both the cookies and allowing me to stay over."

"Okay!" Sayu told him, skipping over to open the door for him, and as he began to shuffle forward, she remembered that she didn't know his name yet. "Oh! Uhm...I don't know your name. What is it? If you don't mind me asking."

He paused, turning towards her and blinking. "My name is Hideki Ryuga," he told her.

Sayu gasped, eyes wide. "Oh my gosh really? That's the name of my favourite pop idol! Whoa, that's so _cool_!"

Her admiration for the weirdo friend of Light's — Hideki Ryuga — instantly became higher, although it wasn't too high to begin with. But he had been kind enough to help her with her homework, so that had to count for something, right?

"I see," he said softly, and finally made it outside. "Goodbye, Yagami-chan."

"Goodbye, Ryuga-kun!" Oh, how she always _wished_ she could say that!

With another grin aimed Hideki's way, Sayu closed the door and reclined against it, clasping her hands together and sighing dreamily.

Sure, she didn't know the actual Hideki Ryuga — well, she didn't know the _idol _Hideki Ryuga, but who cared? She knew _someone_ with that name! She couldn't _wait _to tell her friends tomorrow!

Skipping back into the living room, she grabbed her backpack and bounced up the stairs to get ready for bed, eager for the next day despite the fact that it was a Monday, which meant it would be a school day.

After all, she had some friends to make jealous.

* * *

Having left the Yagami house, L bit his thumbnail, walking towards where Watari had parked the car. It was well away from the house and out of view; the car was one that looked worn and used so it wouldn't attract any unwanted attention. The windows were tinted, which may have aroused suspicion, but the neighbourhood was a safe one. Nobody would really be alarmed by tinted windows here.

Either way, L was right: the car was exactly where he had left it. Finally making it to the car, he opened the car door and shuffled inside, crouching atop the seat and closing the door firmly.

Watari turned in the driver's seat and shot him a kind smile. "Should we get going now, L?" he asked.

L nodded. "Yes."

And they were off.

L shuffled in his seat, placing both hands on his knees, musing about the past forty-seven minutes.

He had done exactly what he had wanted to; he had gone to see what Light's mother and daughter were like. To see if there was any way they knew of the fact that their son was Kira.

His mother had acted completely fine. She had looked a bit disturbed, and her actions a bit forced, but L was sure it was only because of his appearance. She had also only stayed in the kitchen, and by the sounds of it, she was cooking and humming while doing so.

Light's sister was pretty much the same. Put off by who he was, having seen him before like his mother, but surprisingly she had asked him for help with her studies. The questions had been easy enough for him to do in his head in a few seconds flat and easy enough to explain to her, Sayu Yagami, as well.

She hadn't acted the least bit suspicious. And the most astounding thing was that she had...warmed up to him. L was pleasantly surprised by this fact, not having expected it. But it was true. At the end of their encounter, especially after believing his name to be Hideki Ryuga, Sayu Yagami no longer disliked his company. She probably was still a bit put off by his mannerisms, but she held no dislike or disgust for him.

Interesting.

* * *

*okaa-san means 'mother'

**ani-chan means 'older brother'

* * *

**forlornwriter:** _I've written a few L/Sayu fics on my old account, but this is the first time I'm pursuing a short story for the pairing. I don't think it'll be terribly long, as it is a short story. It'll probably be about five chapters, maybe even shorter._

_What I wanted to do with this short story was that I wanted to try and take a creative spin with this short story while also making it something believable and possible. Something that could, maybe, happen in the Death Note manga/anime. I always did think that the couple L/Sayu was interesting, so I went ahead and tried to place the same couple in an almost realistic setting while trying to keep the characters, L and Sayu mostly, in character._

_Sayu acts like your average teen, obsessing over a pop idol as she had in the manga/anime while also thinking L to be weird like one would. L was a bit more difficult to pin down, to be honest. I won't be writing his point of view in the story a lot; in fact, this may be the only time I'll write his point of view. He is a confusing character, but also because the story is more centered around Sayu and her point of view._

_Anywho, moving on. The title is probably kind of cheesy, and I honestly don't like it too much, so I might be changing it. If you guys have any ideas, do let me know!_

_I hope you enjoyed the first chapter, and will stick around for the rest of the story I have planned!_


	2. Physics

**CHAPTER TWO** | _PHYSICS_

It was a week after Sayu saw Hideki last, on a Saturday, that she had to do homework for the weekend again. She thankfully knew better this time, so she had decided to go ahead and start it on Saturday rather than Sunday, and was lying on the couch in the living room with her work splayed out in front of her.

This time, the homework was science. Physics, to be more specific.

Sayu understood a bit of it, but things like scientific notation and whatnot was rather confusing for her.

She had tried to ask Light for help, but lately he had been acting kind of weird; he told her not to bug him with homework and was locking his door so nobody could get in. It was strange, but then again he was finally acting like a real teenager for once in his life, so Sayu couldn't really complain.

Although, she did kind of miss going to him for help. It was the only thing they could actually bond with, even though Light _was _a great brother and all...but she still missed going to him for help and learning something for once.

Plus, her teachers never explained the work so quickly yet fully like Light did. The ideas and stuff always clicked together in her mind when Light taught it to her, making sense. That is, until next time she went to class and the teachers tried to add to a theory or teach something else.

And then Sayu didn't exactly get some concepts again, which frustrated her to no end.

There were times where she wondered why Light couldn't just be her teacher for all of the subjects she had to learn in school, but obviously she knew why. Because he had a life outside of her, his little sister.

And, perhaps, since he was growing older...his life _with _her seemed to be growing smaller and smaller. He was spending less and less time with her. Maybe, one day, he would no longer care about her and stop spending time with her altogether.

Sayu frowned at the depressing thoughts she had stumbled upon and pushed them away, glancing down at her homework and trying to make sense of the questions. Any question she understood the answer to, she quickly scribbled down, but still she had only completed a fourth of all the questions.

"Stupid physics," she said angrily, and was about to try and ask her mother for help-even though Sayu had learned how _great _of a help her mother was, which was truthfully not that much-when the doorbell rang.

"I'll get it, okaa-san," Sayu told her mother, who was slaving away in the kitchen as usual, and got up, eager to get away from her homework for a while.

Opening the door, her eyebrows raised when she realized who it was.

Hideki. He was standing there, weird posture and all.

She grinned. "Ryuga-kun!" Oh, thank _goodness_ he was here! Maybe she could have him help her with her homework?

"Hello, Yagami-chan. I hope you don't mind me dropping in," he said in his usual, emotionless voice.

"No, no! I'm actually kind of...glad," she confessed, making him tilt his head to the side.

"You are? May I ask why?" he questioned. Though his words seemed hostile, Hideki only sounded curious and nothing more.

She rubbed the back of her head sheepishly. "I, uh, need help with some homework again. Ani-chan is here, though! I could get him for you! But...do you mind helping me first? If that's okay?"

He blinked before pressing his thumb to his lips. "Very well. I don't mind."

Sayu grinned at him. "Thank you so much!" she gushed, and allowed him to enter the house, closing the door and skipping into the living room, explaining to him what the subject was and what exactly she needed help with.

Her mother called from the kitchen. "Who was it, Sayu?"

"It's ani-chan's friend! The one who came by last time!"

"O-Oh, I see..." her mother trailed off awkwardly, making Sayu giggle softly to herself. She really didn't seem to like Hideki very much.

Sayu hadn't liked him all that much either, finding him weird, but now he wasn't too bad. He was really nice, helping her out with her homework just because she asked him to. He was still weird, but was more..._endearing_ now.

And kind of cute, in his own way.

Sayu blushed at the strange thought, pushing it away as she sat down and Hideki did the same, though a bit too away from her. She wouldn't be able to show him her work.

"I can't show you my work if you sit that far away," she told him, giggling, and wriggled closer to him.

"I...see. My apologies," he told her, sounding kind of awkward but Sayu brushed it off.

In no time, she was showing him her work and pointing out the more confusing questions, listening intently as he explained them to her. His voice, strangely enough, did not sound as creepy anymore. She had somehow became _used_ to it.

An hour really had made her warm up to him, it seemed. She certainly didn't mind it.

* * *

About half an hour later, Sayu was almost finished her homework, eagerly writing down the answers while Hideki calmly watched. She was making less and less mistakes now, for Hideki had stopped interrupting her while she wrote and telling her that she was writing was incorrect.

"Thanks for much for this, Ryuga-kun," Sayu babbled. "I'm so sorry for using up your time. I know you came here to hang out with my brother and all. It means a lot that you don't mind helping me out with my homework."

"It's no problem, Yagami-chan," Hideki muttered, his hands on his knees, fisting the denim material a bit. "I have no urgent business with your brother currently."

Sayu smiled thankfully at him. "Alright then!" she said cheerfully before going back to answering the questions on the paper.

"That answer is incorrect, Yagami-chan," Hideki told her, so Sayu erased it and bit the eraser on the back of her pencil, pondering over the question and its possible answer.

When the correct answer finally came to her, she jotted it down and looked imploringly at Hideki, silently asking him if the answer was correct. He barely glanced at the paper before nodding his head.

"Great!" she chirped. "You know, you can call me 'Sayu-chan' if you want! I don't mind."

For a few seconds, he stared at her, his wide, coal-coloured eyes boring into her own. Eventually, he nodded his head.

"Very well, Sayu-chan."

Sayu tilted her head, a bit shy now. "Then...may I call you 'Hideki-kun'?" She hoped that she wasn't overstepping any boundaries, asking him if she could be on a first name basis with him.

"Yes, you may do so if you wish," he told her, nodding his head once, not sounding even remotely uncomfortable by her forwardness. There was no emotion in his voice whatsoever, just like usual.

Sayu didn't care, though; she was slowly getting used to it, getting used to _him_.

"Sayu!" Light suddenly called, making Sayu immediately flinch her in seat while Hideki only continued to sit calmly. Light's voice sounded very clear, meaning that he must be standing outside of his room. "Did anyone come to the door some time today?"

He must've been wondering where Hideki was. Sayu bit her lip, feeling guilty for having wasted Hideki and Light's time. But hadn't Hideki told her that he didn't have any urgent business with her brother?

"Yes, Hideki-kun did!" Sayu widened her eyes when she realized that she had just called Light's friend 'Hideki-kun'-to _Light_! He would think something funny was up!

"'Hideki-kun'...?" she could hear him mutter to himself, before he asked her, "Where is he, Sayu?"

"I-In the living room!" she stuttered back, before turning to Hideki apologetically. "You should probably go upstairs to meet with my brother now, Hideki-kun. Sorry for wasting so much of your time."

"It's no problem, Sayu-chan," Hideki told her off-handedly before standing up and making his way to the staircase. Sayu watched him go, and didn't look away until he began to make his way up the staircase, his hands stuffed in the pockets of his baggy jeans.

"Better finish my homework," she mumbled to herself, and began answering questions once more.

She was one hundred percent sure that every single answer she wrote was correct, and it was all thanks to Hideki Ryuga.

* * *

Light was livid. _Extremely_ livid at the idea that L had been in the living room with his sister.

What the hell was he doing there? What questions had he asked her? What if he told her something? His mind was working and processing a mile a second, and Ryuk's raspy laughter did nothing to calm him down. In fact, it only infuriated him further.

He watched, acting as calm as possible, as L appeared at the top of the staircase, and kept his bedroom door open so he could come inside.

"Why were you sitting downstairs with my sister, L?" he asked immediately, eyes narrowed at him.

There was no way L could say that his poking and proding made him more of a candidate to being Kira. One could easily say that his current inquisitiveness was because he was wary about L being near his sister. An overprotectiveness that all older brothers have.

"Nothing having to do with the Kira investigation, I assure you, Light-kun," L said. "I was merely helping her with her homework."

Light shook his head, confused and completely thrown-off. "_Homework_?" he repeated.

"Yes. She had physics homework that she couldn't understand, so she asked me for assistance. She is rather bright for her age. But not as bright as you, of course."

Light blinked. "...okay," he mumbled, sitting down at his desk chair.

So L had only been helping Sayu with her homework. But why would Sayu ask him? Sure, Light told her not to disturb him any more, but why would she ask _L_ of all people to help her? Sayu had always been wary of strangers until she knew them at least a little better.

Could it be that L and Sayu were well acquainted? How long have they known each other? Was today the first time they talked, or have they known one another longer? Light knew that he couldn't continue asking L questions. He might get more suspicious of him or might even lie to him. But Sayu...

He could ask her, and she would tell him truthfully. Because she loved her brother, wouldn't dare lie to him, certainly wouldn't get suspicious of him and his questions.

So, Light would go downstairs and ask her and get all the answers he needed. But he would do so later, when L was gone. And then he'd see if he could use that information to finally dispose of the obstacle in his path to becoming God of the New World: L.

* * *

**forlornwriter:** _Could it be? There actually is going to be a slight plot to this supposedly meaningless short story? It appears to, folks! Well, sort of, haha. I was going to L's point of view at the end instead of Light's, but I found it more interesting if I did Light's, as well as give some information as to what readers should expect in future chapters. And, most importantly, what to expect in the next chapter._

_Will Sayu bring about the death of L earlier than in the canon story? Will Light find anything out about L of value from Sayu? Will L find out Light's plan of getting information about him from his sister? Time will tell._

_No idea yet for a different title for this story, but I'm still thinking of a new one. If you have any ideas, send 'em my way._

_Hope you enjoyed, and do favourite, alert, and/or review if you so wish!_


End file.
